1. Field of the Invention
The present invention relates generally to a mounting structure for a rotary member.
2. Background Information
In a conventional mounting structure for a speedometer drive gear, stopper rings are installed onto the main shaft of the transmission on both sides of the speedometer drive gear in order to prevent the speedometer drive gear from sliding in the axial direction and a ball is installed between a key groove formed in the shaft hole of the speedometer drive gear and a groove portion formed in the main shaft in order to prevent the speedometer drive gear from turning about the main shaft (see, Japanese Examined Patent Application Publication H1-53750 (page 1, FIG. 2)). In such a mounting structure, stopper ring attachment grooves are provided in the main shaft on both sides of the speedometer drive gear mounting position. In order to install the speedometer drive gear onto the main shaft, first, a first stopper ring is installed into the stopper ring installation groove located farther from the installer. Then, the speedometer drive gear is fitted onto the outside of the main shaft and a second stopper ring is installed into the stopper ring installation groove located closer to the installer.